1. Field of the Invention
This invention relates to the field of object-oriented computer graphics and imaging.
2. Background Art
In computer graphics applications there is a technique for combining two images known as "compositing". One example of compositing is the blending of a new screen object of one color with an existing screen object of another color. This color blend is accomplished using a well known compositing technique known as alpha compositing, such as described by T. Porter and T. Duff, "Compositing Digital Images", SIGGRAPH 84, pp. 253-259. A problem with current schemes for providing compositing in computer systems is a difficulty in adding different compositing techniques. Currently, available compositing schemes are hard coded algorithms and are often tied to specific hardware implementations. This discourages or prevents the addition of customized compositing schemes.